What is the error actually? Can you please provide us a temporary access to your site so that we can try importing the demo content?
Also can you please check & let us know if you’re using the latest version of PHP on your server or not?

OK, I solved the problem, can you tell me how to modify the picture (home slide)? I imported the template.

Well it’s a good news that you’ve solved the demo importer issue by your own. By the way I think you’re asking about the homepage slider so you can modify it by going to Teriz Slider. Then you need to set the category to each slider. After you assign a category then you’ll be able to set the category on the meta option of pages which shows after the content. There you’ll be able to enable or disable the slider or choose which categorized slider you want to load on homepage.

Hopefully this information will help you.

Thanks & Best Regards

Thank you, OK.